Ammonia—a renewable fuel made from sun, air, and water—could power the globe without carbon

All told, Australia boasts a renewable energy potential of 25,000 gigawatts, one of the highest in the world and about four times the planet’s installed electricity production capacity. Yet with a small population and few ways to store or export the energy, its renewable bounty is largely untapped.

That’s where MacFarlane comes in. For the past 4 years, he has been working on a fuel cell that can convert renewable electricity into a carbon-free fuel: ammonia.